High‐Performance Monolayer 1T‐GeO2 Transistors with Low‐Resistance Metal Contacts

Abstract

As silicon‐based electronics approach their scaling limits in the post‐Moore era, 2D semiconductors offer a promising path forward. In this study, first‐principles calculations are employed, combined with quantum transport simulations to predict that monolayer 1T‐phase germanium dioxide (1T‐GeO2) is an exceptional channel material due to its favorable metal–semiconductor interface properties. Through systematic contact engineering analysis, it is revealed that conventional metals—including Au, Pt, Pd, Ag, Ti, In—form ideal Ohmic contacts with 1T‐GeO2, exhibiting ultralow contact resistances of 35.33–54.03 Ω·µm. Notably, these simulations predict that 1T‐GeO2‐based field‐effect transistors (FETs) with Pd, Au, Ti, and Pt contacts exhibit ultrahigh on‐state currents of up to 1151–3237 nA nm−1 at an 8.5 nm channel length, surpassing the 2028 performance targets set by the International Roadmap for Devices and Systems (IRDS). These performance advantages originate from the intrinsic electronic properties of the metal/1T‐GeO2 interfaces, including small electron effective mass, weak Fermi‐level pinning, moderate orbital overlaps, absence of Schottky barriers, and low tunnel barriers, which enable both efficient carrier injection and excellent channel transport. These results suggest that 1T‐GeO2 is a leading 2D semiconductor candidate for scalable, high‐performance, and energy‐efficient transistors beyond conventional silicon technology.